Seriously?, you seem pretty young, but you do understand that Dole and McCain were both very prominent opponents of the "Bush wing" of the party, right? The TP/establishment divide is a product of the Obama era that was not visible prior to ~2009, and trumpist personal movement dates all the way back to 2015.
Seriously?, the key divide in 2000 was that Bush was seen as a conservative, whereas McCain explicitly ran as a moderate. McCain ran as a moderate a second time in 2008, when the vote to his right was divided by Huckabee and Romney until it was far too late to stop McCain. It should be noted, however, that the conservative/moderate divide that existed prior to the TP/establishment divide was much less fractious than the current divide that exists -- nominees generally didn't have significant issues getting the other side to back them.
As far as Dole goes. He's also not a conservative in the mold of Reagan. He was Ford's running mate in 1976 (anti-Reagan) and at the time of his run against Clinton in 1996 was as establishment as you can get as the Senate Majority Leader. While he may have been good at building consensus between the conservative and moderate wings of the party, Dole never had a conservative voting record.
As far as Dole goes, he was chosen as VP nominee by Ford in order to placate the conservative wing, much as Palin was chosen in 2008 (although he ended up having more lasting power than Palin). Dole also ran against Bush in 1988 from the right. It's important to keep in mind when you talk about the Bush wing that the older Bush was generally associated with the moderate wing of the Republican Party, whereas the younger Bush was usually associated with the conservative wing.
"Establishment" in 1996 was not the same thing as "establishment" in 2016. The key divide in 1996 was
within the establishment (moderate vs. conservative, and while anti-establishment candidates were already running (as early as 1988, with Pat Robertson; in 1996, you had Pat Buchanan and Steve Forbes), they generally didn't get anywhere because anti-establishment sentiment was not widespread in the party at that time, and it didn't become widespread until after Obama's election in 2008.
The fact of the matter remains that in this cycle, the establishment/Bush wing of the party has been rejected by the voters. If a contested convention happens and someone from the establishment wing like Paul Ryan -- or even worse -- Mitt Romney ends up being the nominee, the party will be destroyed from within.
I think it's very clear that a contested convention is going to nominate Ted Cruz and that very likely no one will get drafted. Even if someone does get drafted (if Kasich is kept off the Ballot through use of Rule Forty, his adherents abstain
en masse, and there aren't enough defectors from
trump to give Cruz the nomination, we'd see attempts at drafting someone), that person will only approach the nomination if they manage to get Cruz's support or
trump's, for the simple reason that Cruz loyalist delegates +
trump loyalist delegates are going to be an overwhelming majority of the convention.
